In this case, fear of puppies is a good thing, because it will keep them for being aggressive.
This is how I usually intoduce new dogs (and I do it a lot, since I always have foster dogs coming in and out of my house):
We introduce them at a park, or somewhere where the older dogs do not feel like they own the property. I'll set up an ex-pen, where the new dog will be. I'll introduce the alpha dog of the older group through the ex-pen. If the they get along well, I'll take the new dog out of the ex-pen and let them sniff and get to know each other for a few minutes. Then, I'll put the new dog back in the ex-pen and keep the first older dog outside with me as I one-by-one introduce the older dogs. Usually everything goes well, so I'll let the new dog out of the ex-pen and let them all sniff and get to know each other.
When I take them all back home, I keep a very close eye on them, and don't leave them all alone together.
Make sure you give your older dogs A LOT of attention, and have some alone time away from the new puppies.
__________________  Anna and  Wobie |